Viscount Mayo

{{Short description|Title twice created in the Peerage of Ireland}}

{{Use dmy dates|date=April 2022}}

{{Infobox nobility title

| name = Viscountcy of Mayo
Bíocuntacht Mhaigh Eo

| image = File:Coronet of a British Viscount.svgFile:Arms of Bourke, Earl of Mayo.svg

| image_size =

| alt =

| caption = Arms: Per fess Or and Ermine, a Cross Gules, in the 1st quarter a Lion rampant and in the 2nd a dexter Hand affrontée, both Sable. Crest: On a Chapeau Gules, turned up Ermine, a Lion sejant Argent, langued Gules, ducally gorged Or. Supporters: Dexter: A Harpy guardant wings and lions body Or, human face neck chest and hair proper, armed Gules; Sinister: A Man in Armour to the middle of his thigh, Sword proper, suspended from a Belt Gules, about his head a square White Band, sandles Sable, in the exterior hand a Battle-Axe proper.{{Cite book |last=Burke |first=Bernard |author-link=Bernard Burke |url=http://archive.org/details/generalarmoryofe00burk |title=The General Armory of England, Scotland, Ireland, and Wales; comprising a registry of armorial bearings from the earliest to the present time |date=1884 |publisher=Harrison & Sons |location=London |others=University of California Libraries}}

| creation_date = 21 June 1627

| creation = First

| monarch = King Charles I

| peerage = Peerage of Ireland

| baronetage =

| first_holder = Tiobóid na Long Bourke, 1st Viscount Mayo

| last_holder = John Bourke, 8th Viscount Mayo

| present_holder =

| heir_apparent =

| heir_presumptive =

| remainder_to = The 1st Earl’s heirs male of the body lawfully begotten

| subsidiary_titles = Baronet ‘of Mayo’
Baronet ‘of Brittas’

| status = Extinct

| extinction_date = 12 January 1767

| family_seat =

| former_seat =

| motto = AUDACES FORTUNA JUVAT
(Fortune favours the brave){{Cite book |last=Burke |first=Bernard |author-link=Bernard Burke |url=http://archive.org/details/generalarmoryofe00burk |title=The General Armory of England, Scotland, Ireland, and Wales; comprising a registry of armorial bearings from the earliest to the present time |date=1884 |publisher=Harrison & Sons |location=London |others=University of California Libraries}}

| footnotes =

}}

Viscount Mayo ({{Langx|ga|Bíocunta Mhaigh Eo}}) is a title that has been created twice in the Peerage of Ireland, both times for members of the Bourke family. The first creation came in 1627 in favour of Tiobóid na Long Bourke, also known as Theobald Bourke. He was the son of Sir Richard Bourke, 18th lord of Mac William Iochtar (Lower Mac William), and Gráinne O'Malley. Miles, the 2nd Viscount, was created a baronet in the Baronetage of Nova Scotia in c. 1638.

His son Theobald, the third Viscount, was also created a Baronet in the Baronetage of Nova Scotia in c. 1638 (although there are no records of this creation in the Great Seal). The third Viscount was executed in 1652 after being found guilty of murder by Cromwell's High Court of Justice in Connaught. The murders in 1642 became known as the "Shrule massacre", but it seems that Lord Mayo had done his best to prevent them.[http://1641dep.abdn.ac.uk/items/show/42344 Deposition of Theobald, 3rd viscount, sworn Nov. 1652 (accessed online 17 Oct 2016)]

The third Viscount's daughter Maud married Col. John Browne, ancestor of the Marquesses of Sligo.{{cite book |last=Burke |first=John |author-link=John Burke (genealogist) |title=A Genealogical and Heraldic History of the Commoners of Great Britain and Ireland Enjoying Territorial Possessions Or High Official Rank: But Uninvested with Heritable Honours: Volume 1 |publisher= |location=London |year=1836 |pages=67–69 |url=https://books.google.com/books?id=FOVsAAAAMAAJ}}

On the eighth Viscount's death in 1767, the title became dormant or extinct.{{cite book |last=Cokayne |first=G. E. |author-link=George Edward Cokayne |title=The Complete Peerage of England, Scotland, Ireland, Great Britain, and the United Kingdom Extant, Extinct, or Dormant |title-link=The Complete Peerage |publisher=George Bell & Sons |location=London |year=1893 |edition=1st |volume=5 |pages=[https://archive.org/details/completepeerage01cokagoog/mode/2up?view=theater 278-80] |language=en}} Historian Anne Chambers considers that a legal right continued, but that the next claimant could not afford the legal costs involved in presenting a petition to the Irish House of Lords.{{cite book |last=Chambers |first=Anne |title=Shadow Lord: Theobald Bourke, Tibbott-Na-Long, 1567–1629: Son of the pirate queen Grace O'Malley |publisher=Ashfield Press |location=Dublin |year=2007 |isbn= 978-1-901658-65-1 |language=en}}

The title was recreated for a very distant cousin, John Bourke, 1st Baron Naas, in 1781. He was subsequently created Earl of Mayo in 1785. See this title for more information.